Internal-combustion engine



Aug. 24,1926. 1,597,264

F. CARTER Er AL INTERNAL COMBUSTION ENGIN E File 9 1925 2 Sheets-Sheet 1Fig.1.

' 'mmzy Aug. 24, 1926. 1,597,264

F. CARTER ET AL INTERNAL COMBUSTION ENGINE Filed Dec. 16, 1925 2Sheets-Sheet 2 A '1 B Fig.3.

. wmvrons ffeaA/nr 69/8752, flE/QZVCE/GTE firronmrr starts tnamt AWE)EVERSHIED CARTER, @Ii ESTAMFORD, LINCOLN, ENGLAND, AS- EESKGNWES FONE-THIRD T0 GEORGE MILLS BLACKSTONE, 0F STAMFORD, LINCOLN,

INTERNALCOMBUSTIOH ENGINE.

Application filed December 16, 1925, Serial No. 75,823, and in GreatBritain November 2'5, 1924.

'Our invention relates primarily to the combustion chambers of verticalinternal combustion engines of the kind in which the air is compressedto high pressure and temperature sufficient to ignite the fuel which issprayed into the compressed charge without the use of spraying air.

In connection with the injection of fuel into the compressed air in theabove man- W ner, the following considerations appear to us to beimportant.

W hen a jet of fuel leaves the nozzle it is comparatively cold. At somepoint in its path, however, it has acquired sufiicientheat to begin tovapourize, and at a further point in its path 'it is completelyvapourized. Each jet assumes a theoretically conical shape by theproduction of a surrounding fringe of vapour increasing in width alongits path. The vapour fringe requires air to burn in over all itssurface, but a supply of air adjacent the unvapourized jet isunproductive of any increment of power and tends merely to diminish theeffectiveness of 35 the force of the explosion.

The ideal explosion chamber determined solely in accordance with theabove would appear to have a spherical wall opposite the jet nozzle andpositioned at the region where the liquid fuel becomes completelyvapourized, the area of the wall being determined by the necessity forproviding a fringe of air outside the conical streams of vapour at thesaid region and the angle of 35 spread of the jets. If the vapour jetsof a multiple-orifice nozzle are arranged as closely as possible to theaxis of the mean path (leaving however suflicient air between the vapourfringes for the latter to burn freely on their inner surfaces) thesphericality of the surface will tend to become more nearly plane; andin practice said wall can conveniently be made plane and its shape mayconveniently be a regular polygon, i. e., if I four jets are employed itmay be square with the jets directed to points on the diagonalsspaced'inwardly from the angles of the square.

It is further generally desirable in internal combustion engines thatthe exhaust valve reciprocates vertically so as to facilitatelubrication and avoid distortion under heat due to the weight of thehead, and also that the port for said valve be formed ina plane surface,and the present invention has for its object to provide in verticalengines a form of cylinder head wherein the above conslderations aresuitably embodied or to a large extent reconciled by an effectivecompromise, having regard also to various plifficulties requiring to bemet in manufacure.

According to the invention the combustlon chamber in such enginescomprises a rectangular chamber having in one vertical wall a pocket orrecess in the remote end of which is seated the injector nozzle, therectangular" base of the main portion of the combustion chamberco-operating with a turbulence block preferably comprising a rectangularextension on the piston top having small and generally rectangular partscut away at two opposite corners in order to produce rapidly-movingcolumns of air adapted to set up turbulence within the compressed chargein the combustion chamher. The rectangular element of the combustionchamber preferably approximates to a cube with the addition ofadditional width in one horizontal dimension corresponding to the widthof the aforesaid ports or cut away parts in the head of the turbulenceblock. This additional width may approximate to 20% increase over theother a horizontal dimension, and is transverse to the mean path of thefuel.

The injector nozzle is adapted to inject preferably four pencils of fuelfrom the bottom of the recess across the rectangular chamber, thelimiting orifices being directed generally towards the diagonals of theopposite wall which is also rectangular, and the cone of the recessbeing no larger than is necessary to give clearance to the said jets.The upper horizontal wall or roof of the combustion chamber is ported,and the exhaust valve reciprocates vertically in connection with thesaid port. The vertical wall of the rectangular combustion chambersituated opposite to the jets maybe ported for the admission of air, theport being controlled by an inlet valve. Alternatively the said wall maybe lain, the admission of an being controlled y a transfer valve 1n abifurcation of the passage leading from the port in the upper wallcontrolled by the vertically reciprocating valve. 7

llhe invention is illustrated in the accompanying drawings, in which 3-Fig. 1 shows a cross-section view of the cylinder head and valvemechanism.

Fig. 2 is a plan of a detail. Fig. 3 is a crank shaft diagram.

Figs. 4 to 7 illustrate the movements of the cylinder and transfervalves, and

Fig. 8 is a modification of Fig. 2.

Referring. to the drawings, the c ombus tion chamber 1, as illustratedin F1g. 2 1s rectangular in plan and cooperates w1th a turbulence block2 which is mounted on the piston 3 and is generally rectangular in plan,but has parts cut away at opposite corners, as illustrated at 4, inorder to produce rapidly-moving columns of air adapted to set upturbulence within the compressed charge in the combustion chamber. Thedimensions of the block and the combustion chamber preferablyapproximate to a cube having additional width in one horizontaldimension by an amount equal to the width of the cut awayparts 4:.

The fuel valve 5 is seated at the bottom of a recess 6 having a conicalenlargement at its forward end formed in a vertical wall of thecombustion chamber 1, and the exhaust valve 7 reciprocates vertically ina port 8 in the roof of the combustion cham- In the preferred form asshown in full lines in Fig. 1 the exhaust valve 7 serves also foran airinlet valve, the port 8 be ing opened to air and exhaust alternatelybymeans of a transfer valve 9 seated behind the cylinder valve 7.Alternatively, we may dispense with the transfer valve and pro-' vide aseparate air inlet valve 10 as indicated in dotted lines in Fig. 1.

In the preferred form, the cylinder valve 7 is driven through a rockerby means of a cam 11 rotated by a shaft 12 moving at half engine speedand the transfer valve 9 is driven through a rocker by means of aneccentric 13 on the shaft 12.

In operation, assuming the piston is at the top of its compressionstroke, the valves 7 and 9 will be in the position illustrated in Fig.4, in which the port 8 is closed by the valve 7 and the valve 9 is inits cen tral position. It should here be noted that the operative faceof the valve 9 is slightly narrower than the common port 14, so that thevalve in the said position admits of communication from the port 8 bothto air mlet and to exhaust, the valve 9 being now moved upwardly so thatthe exhaust opening is in process of enlarging.

A charge is now fired and the piston moves down, the cylinder valve 7beginning to open when the piston is about 45 degrees infront of thebottom dead centre (as indicated at TV in Fig. 3), by which time thevalve 9 has moved upwardly approximately clear of the port 14% into theposi tion shown in Fig. 5. Exhaust now commences and the valve 7continues to open until it reaches the position shown in dotted lines inFig. 5, which is approximately 45 degrees after bottom dead centre, andis indicated at V in Fig. 3. The valve 9 is now moving downwardly, andwhen the piston reaches the top of the exhaust stroke, its

position is as illustrated in Fig. 6, accord ing to which the port 8 isopen both to air and exhaust, owing to the. relatively narrow face ofthe va ve 9 compared with the opening of the port 14. By thisarrangement any momentum that may be left in the exhaust gases will tendto draw in air from the air inlet and sweep out the passage between theports 8 and 14. As the p-iston moves down, the exhaust is quickly closedby the valve 9, the points at which air is opened and exhaust is closedbeing indicated at A and B respectively in Fig. 3. and remains openthroughout the suction stroke till the piston reaches the bottom deadcentre to which F i 7 corresponds, at which point the valve l' has movedupwardly considerably as indicated, being finally closed at the pointindicated at C in Fig. 3 early in the compression stroke.

It will thus be realized that in the form already described, thecylinder valve remains open for about 420 degrees of the crank shaftmovement under the action of the cam 11. In the modification. in which aseparate air inlet valve 10 is employed, the cam 11 would require to becut down by about 90 degrees on the cam shaft and the air inlet valve 10could be operated by a cam similar to the modified cam 11.-

It is to be understood that the dimensions of the free space in thecombustion chamber, as illustrated in Fig. 1, are such that the outerfringes of the limiting jets of fuel are directed generally to thecorners of the opposite wall of the combustion chamber and that theconicity of the forward part of the recess 6 is limited to giving thenecessary clearance to these jets. The fuel valve nozzle is setback tosuch a distance as to permit of an eflicient throw and spread of thefuel jets to ensure complete combustion without the deposit of liquidfuel on the opposite wall, a suitable angle of spread being 18 away fromthe mean axis of the nozzle. The turbulence ports 4 situated at oppositecorners are so arranged as to secure the necessary turbulence withoutdirectin the air currents in such a manner that t ey' will directlyinterfere with the normal throw of fuel from the jets, i. a, they willclear the fringes. It is, of course,

The valve 7 has not yet'been movedinterest necessary that the totalvolume of the combustion chamber relatively to the diameter and strokeof the piston 3 are such as to ensure high compression of the chargenecessary to produce eflicient ignition of the fuel. In practice, with acombustion chamber shaped as described, the area of the rectangular partmay be about one-quarter the area of the piston.

In the modification shown in plan in Fig. 8, the combustion chamber 1 isshaped as in Fig. 2, but the turbulence block 22 is circular and comesup through a circular hole 23 in a transverse web 24 formed at thebottom of the combustion chamber. The circular block 22 is not ported,but holes 25 are formed in the web through which jets of air are forcedby the piston to give the desired turbulence. v

This modification is intended for use with an exhaust valve larger thanthat illustrated in Fig. 1 and larger in area than in the hole in theweb 24 so that if the valve stem breaks, the head will not fall downinto the cylinder but will be caught by the webv and thus avoid orminimize consequent damage.

Obviously thehole and turbulence block in this, modification may takeother shapes than circular.

Although we have illustrated the preferred form of the inventionhitherto. constructed, it will be realized that the particulardimensions of the throw and spread of the fuel may be varied inaccordance, for example, with the injector pressure and the pressure ofairin the cylinder head.

I claims- 1. In an internal combustion engine, a c linder having itsaxis vertical, a rectangu ar combustion chamber at the top of saidcylinder, the area of'said chamber being considerably less than that ofsaid cylinder, a piston, a turbulence block 'on said piston, said blockbeing shaped to allow clearance for vertical turbulence jets between itand the wall of the combustion chamber, a recess in a vertical wall ofsaid chamber, and a fuel delivery nozzle set back in said recess.

2. 'In an internal combustion engine, a cylinder having its axisvertical, a rectangular combustion chamber at the top of said cyl--inder, the area of said chamber being considerably less than that ofsaid cylinder, a PlStOIl, a turbulence block on said piston, said blockbeing shaped to allow clearance for vertical turbulence jets between itand the wall of the combustion chamber, a recess in a vertical wall ofsaid chamber, and a fuel delivery nozzle set back in said recess, aportin the roof of said chamber for the exhaust I of the combustionproducts.

3. In an internal combustion engine,"'a cylinder having its axisvertical, a rectangular combustion chamber at the top of said cylinder,the area of said chamber being'considerably less than that of saidcylinder, a piston, a turbulence block on said piston, said block beingshaped to allow clearance for vertical turbulence jets between it andthe wall of the combustion chamber, a recess in a vertical wall of saidchamber, a fuel delivery nozzle set back in said recess, a port in theroof of said chamber for the exhaust of the combustion products and forthe inlet of air, a bifurcated passage leading from said port, and atransfer valve governing said bifurcation.

4. In an internal combustion engine, a cylinder having its axisvertical, a rectangular combustion chamber at the top of said cylinder,the area of said chamber being considerably less'than that of saidcylinder, a piston, a turbulence block on said piston, means whereby atthe top of the stroke of said piston said chamber is only partiallyclosed by said turbulence block so t at turbulence jets are produced bythe stroke of said piston, a recess in a vertical wall of said chamber,and a fuel delivery nozzle set back in said recess.

5. In an internal combustion engine, a cylinder having its axisvertical, a rectangular combustion chamber at the top of said cylinder,the area of said chamber being consideraly less than that of saidcylinder, a pisston, a turbulence block on said piston, means whereby atthe top of the stroke of said piston said chamber is only partiallyclosed by said turbulence block so that turbulence jets are produced bythe stroke of said piston, a recessin a vertical wall of said chamber, afuel delivery nozzle set back in said recess, and a port in the roof ofsaid chamber for the exhaust of the combustionproducts.

6. In aninternal combustion engine, a cylinder having its axis vertical,a rectangular combustion chamber at the top of said cylinder, the areaof said chamber being considerably less than that of said cylinder, apiston, a turbulence block on said piston, means whereby at the top ofthe stroke of said piston said chamberis only partially closed by saidturbulence block so that turbulencejets are produced by the stroke ofsaid piston, a recess in a vertical wall of said chamber, a fueldelivery nozzle set back in said recess, a port in the roof of said.

chamber for the exhaust of the combustion products and for the inlet ofair, a bifurcated passage leading from said port, and a transfer valvegoverning said bifurcation.

7. In an internal combustion engine, a cylinder having its axisvertical, a rectangular combustion chamber at the top of said cylinder,the area of said chamber being considerably less than that of saidcylinder, a piston, a turbulence block on said piston shaped generallyto conform to the shape of said chamber but having cut away parts atopposite angles, a recess in a vertical wall of said chamber, and a fueldelivery nozzle set back in said recess.

8. In an internal combustion engine, a cylinder having its axisvertical, a rectangular combustion chamber at the top of said cylinder,the area of said chamber being considerably less than that of saidcylinder,

7 a piston, a turbulence block on said piston,

shaped generally to .conform to the shape of said chamber but having cutaway parts-at opposite angles, a recess in a vertical wall of saidchamber, a fuel delivery nozzle set back in said recess, and a port inthe roof of said chamber for the exhaust of the combustion products.

9. in an internal combustion engine, a cylinder having its axisvertical, a rectangular combustion chamber at the top of said cylinder,the area of said chamber being considerably less than that of saidcylinder, a piston, a turbulence block on said piston, shaped generallyto conform to the shape of said chamber but having. cut away parts atopposite angles, a recess in a vertical wall of said chamber, a fueldelivery nozzle set back in said recess, a port in the roof of saidchamber for the exhaust of the combustion products and for the inlet ofair, a bifurcated passage leading from said port, and a transfer valvegoverning said bifurcation.

10. In an internal combustion engine, a cylinder, a combustion chamber,a piston, a

turbulence block, the area of said chamber and block generallyconforming and approximating to a rectangle havlng an appreciable' difierence in its majorand minor dimensions, the block being cut away atopposite corners to a depth approximating the difference between themajor and minor dimensions of the block.

11. In an internal combustion engine, a

cylinder, a combustion chamber, a piston,

a turbulence block, the area of said chamher and block generallyconforming and approximating to a rectangle having an appreciabledifierence in its major and minor dimensions, the block being cutaway atopposite corners to a depth approximating the difference between themajor and minor dimensions of the block, the height of the ,coinbusti on7 chamber corresponding to the wall of the combustion chamber, a recessin a vertical wall of said chamber, a fuel delivery nozzle set back insaid recess and having four divergent orifices directed to the diagonalsof the free area ofthe opposite rectangular wall which is left uncoveredby the turbulence block.

' In testimony whereof we a'fix our signatures.

- FRANK CARTER,

' EVERSHED CARTER.

